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Analysis of the Influencing Factors of Changes in Foxtail Millet Planting Area in Hebei Province 被引量:2
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作者 Meng LIU Yu ZHAO +3 位作者 Fei LIU Shunguo LI Guirong WANG Xinshi ZHANG 《Asian Agricultural Research》 2013年第3期30-34,共5页
Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In t... Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training. 展开更多
关键词 MILLET area CHANGES Influencing FACTORS Osculating
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Effects of Different Modes of Returning Farmland to Forest on Physicochemical Properties of Soil in Bashang Area of Northern Hebei Province
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作者 Yue YANG Yitian YANG +2 位作者 Zhiyong WU Caiwu WU Yongjiao HAN 《Meteorological and Environmental Research》 CAS 2020年第4期98-102,共5页
[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three differe... [Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best. 展开更多
关键词 Returning farmland to forest Physicochemical properties of soil Bashang area of northern hebei province
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The Analysis of Limitation of Engel's Coefficient——A Case Study of Rural Areas in Hebei Province
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作者 HAO Jun1,LIU Jie2 1.Shijiazhuang Postal Vocational and Technical College,Shijiazhuang 050021,China 2.Business School,Hebei Normal University,Shijiazhuang 050024,China 《Asian Agricultural Research》 2011年第4期24-29,共6页
On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,n... On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,not in line with reality of China;comparison invalidity in length and breadth,is not conducive to relevant analysis;culling out the special factors easily causes distortion of conclusion.Taking rural areas in Hebei Province as an example,this paper analyzes the limitation of Engel's coefficient in analyzing the gap of rural economy:in terms of region horizontally,Engel's coefficient neglects the difference of consumption structure among regions,and difference of economic stages among regions;in terms of time vertically,Engel's coefficient neglects the periodic change of consumption structure and the ratio change of different families in different periods.According to the reality of China's rural areas,the correction model of Engel's coefficient is established as follows.Firstly,Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of total expenditure variation;Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of income variation.Secondly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of variation of(total expenditure educational expenditure-medical expenditure.Thirdly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of total expenditure variation. 展开更多
关键词 Engel’s COEFFICIENT DIFFERENCE of CONSUMPTION stru
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Process and mechanism of arable land change in Hebei Province during the past 50 years 被引量:3
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作者 XU Yue-qing (Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期47-52,共6页
Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with pop... Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable development.This paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc. 展开更多
关键词 decrease in arable land area changing process mechanism hebei province
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Terrestrial water storage variation in Hebei plain area of China,based on ground surface gravimetry 被引量:1
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作者 Hongtao Hao Hongliang Liu +3 位作者 Xinlin Zhang Jin Wei Bin Zhao Minzhang Hu 《Geodesy and Geodynamics》 CSCD 2021年第3期190-196,共7页
Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Resu... Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Results show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land subsidence.With the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic data.These results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water. 展开更多
关键词 hebei plain area Gravity variation Terrestrial water storage variation Ground surface gravimetry Land subsidence
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Analysis on Temporal and Spatial Changes and Driving Forces of Poverty-Stricken Areas in Hebei Province
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作者 Shi Xiaoli, Yuan Jinguo & Wang WeiCollege of Resources and Environmental Sciences, Hebei Normal University, Shijiazhuang 050016,China 《Chinese Journal of Population,Resources and Environment》 北大核心 2005年第2期42-48,共7页
关键词 Poverty-stricken areas temporal andspatial changes hebei province driving forces
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Metabasic Dyke Swarms in a High-Grade Metamorphic Terrane——A Case Study in the Taipingzhai-Jinchangyu Area,Eastern Hebei Province
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作者 Chen Manyun Changchun College of Geology Zhang Zhongmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第4期427-441,467,共16页
Geological and petrological studies indicate that three phases of metabasic dykes are present in theTaipingzhai-Jinchangyu area within the high-grade metamorphic terrane of eastern Hebei. Garnet andhornblende in metab... Geological and petrological studies indicate that three phases of metabasic dykes are present in theTaipingzhai-Jinchangyu area within the high-grade metamorphic terrane of eastern Hebei. Garnet andhornblende in metabasic dykes of the second and third phases occur separately, forming two mineral aggregateareas gl+cpx+pl±hy and hb+cpx+pl-hy. P_(H_2O) in the rocks appears to be the main factor controlling theformation of the two aggregate areas. Both were formed simultaneously at the same metamorphic temperature. The second-phase basic dykes underwent metamorphism of pyroxene-granulite facies at a temperature ofsome 825C: later the dykes, together with the third-phase basic dykes experienced metamorphism ofamphibole-granulite facies at a temperature of about 750C under pressure of 0.9GPa. 展开更多
关键词 A Case Study in the Taipingzhai-Jinchangyu area Eastern hebei province Metabasic Dyke Swarms in a High-Grade Metamorphic Terrane
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Problems and reconstruction of the development of rural preschool education in Hebei Province
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作者 Yang Huiliang Hou Jiaying 《International English Education Research》 2015年第5期90-91,共2页
关键词 教育发展 农村 河北省 学前教育 城乡一体化 市场经济 幼儿教育
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冀北上黄旗地区多金属矿成矿规律与矿产预测
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作者 高攀 张有军 +3 位作者 刘战鹏 王鹏飞 李继业 李松彬 《地质找矿论丛》 CAS 2024年第1期35-44,共10页
冀北上黄旗地区位于华北地台北缘中段成矿带及兴安太行南段成矿带的相交区域,是华北地区著名的(银)多金属成矿区。本文在综合分析区域成矿地质背景、成矿地质条件、地球物理、地球化学、遥感异常特征及成矿规律的基础上,认为该区具有寻... 冀北上黄旗地区位于华北地台北缘中段成矿带及兴安太行南段成矿带的相交区域,是华北地区著名的(银)多金属成矿区。本文在综合分析区域成矿地质背景、成矿地质条件、地球物理、地球化学、遥感异常特征及成矿规律的基础上,认为该区具有寻找侵入岩型和陆相火山岩型两大类多金属矿床的有利条件,划分出3条Ⅳ级成矿亚带,圈定成矿远景区10个。其中,A类4处,B类4处,C类2处;并优选出多金属矿找矿靶区7个,A类4个,B类2个,C类1个。 展开更多
关键词 多金属矿 成矿远景区 找矿靶区 上黄旗地区 冀北
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Impact of the shrinking winter wheat sown area on agricultural water consumption in the Hebei Plain 被引量:17
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作者 WANG Xue LI Xiubin XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期313-330,共18页
This study firstly analyzed the shrinkage of winter wheat and the changes of crop- ping systems in the Hebei Plain from 1998 to 2010 based on the agricultural statistic data of 11 cities and meteorological data, inclu... This study firstly analyzed the shrinkage of winter wheat and the changes of crop- ping systems in the Hebei Plain from 1998 to 2010 based on the agricultural statistic data of 11 cities and meteorological data, including daily temperature, precipitation, water vapor, wind speed and minimum relative humidity data from 22 meteorological stations, and then calcu- lated the water deficit and irrigation water resources required by different cropping systems, as well as the irrigation water resources conserved as a result of cropping system changes, using crop coefficient method and every ten-day effective precipitation estimation method. The results are as follows. 1) The sown areas of winter wheat in the 11 cities in the Hebei Plain all shrunk during the study period. The shrinkage rate was 16.07% and the total shrinkage area amounted to 49.62×10^4 ha. The shrinkage was most serious in the Bei- jing-Tianjin-Tangshan metropolitan agglomerate, with a shrinkage rate of 47.23%. 2) The precipitation fill rate of winter wheat was only 20%-30%, while those of spring maize and summer maize both exceeded 50%. The irrigation water resources demanded by the winter wheat-summer maize double cropping system ranged from 400 mm to 530 mm, while those demanded by the spring maize single cropping system ranged only from 160 mm to 210 ram. 3) The water resources conserved as a result of the winter wheat sown area shrinkage during the study period were about 15.96×10^8 m^3/a, accounting for 27.85% of those provided for Beijing, Tianjin and Hebei by the first phase of the Mid-Route of the South-to-North Water Diversion Project. 展开更多
关键词 irrigation water resources winter wheat sown area shrinkage crop water consumption hebei plain
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海域资源资产收益管理和分配研究——以河北省为例
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作者 沈佳纹 谷青华 +4 位作者 霍永伟 田洪军 张慧 曹英志 李亚宁 《中国国土资源经济》 2024年第6期59-66,共8页
健全完善海域资源资产收益管理和分配制度是自然资源资产产权制度改革的关键环节,也是全民所有自然资源资产所有权委托代理机制试点工作的重点内容。文章系统梳理了海域资源资产收益来源、收益形式、收益征收管理和分配现状,并以河北省... 健全完善海域资源资产收益管理和分配制度是自然资源资产产权制度改革的关键环节,也是全民所有自然资源资产所有权委托代理机制试点工作的重点内容。文章系统梳理了海域资源资产收益来源、收益形式、收益征收管理和分配现状,并以河北省为例,探讨了当前海域资源资产收益管理与分配中存在的问题:①资产配置以行政手段为主,市场化水平不高;②海域使用金征收标准偏低,资产收益实现形式单一;③资产收益分配不合理,央地财政事权划分不匹配。基于此,文章提出在分级行使海域资源资产所有权模式下完善收益管理和分配制度的对策建议:①深化海域有偿使用制度改革;②完善海域资源资产收益管理路径,合理划分财权事权;③强化预算管理;④建立收益管理成效评价机制。 展开更多
关键词 海域资源资产 收益管理 收益分配 河北省
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冀北山地桦木林土壤细菌群落特征对坡向的响应
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作者 于小萌 高青青 +3 位作者 许竹锐 马旭满 孟亚馨 徐学华 《林业与生态科学》 2024年第3期288-296,共9页
为了揭示冀北山地桦木林土壤细菌群落特征对坡向的响应规律,以冀北山地阴坡、半阴坡和半阳坡桦木林土壤为研究对象,采用高通量测序技术,分析了土壤细菌群落结构和多样性。结果表明:细菌群落组成主要包含41门、107纲,其中优势细菌门为变... 为了揭示冀北山地桦木林土壤细菌群落特征对坡向的响应规律,以冀北山地阴坡、半阴坡和半阳坡桦木林土壤为研究对象,采用高通量测序技术,分析了土壤细菌群落结构和多样性。结果表明:细菌群落组成主要包含41门、107纲,其中优势细菌门为变形菌门和酸杆菌门;土壤细菌群落α多样性指数在坡向间存在显著差异,阴坡>半阴坡>半阳坡;土壤含水量、容重、硝态氮和氨态氮均影响细菌微生物群落的结构组成,其中,土壤含水量与多种细菌门存在显著相关性,且与细菌α多样性存在极显著的正相关性。综上所述,不同坡向桦木林土壤细菌群落结构和多样性呈现出一定的变化规律,坡向和土层深度变化引起的土壤含水量变化是该地区桦木林土壤细菌群落结构和多样性差异的主要因素。 展开更多
关键词 桦木林 坡向 土壤细菌 群落多样性 冀北山地
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河北省典型铅锌矿区重金属来源解析及生态风险评价
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作者 刘安 于聪灵 +4 位作者 王立平 宋娟娟 孙连伟 金倩 孙孟华 《地质科技通报》 CAS CSCD 北大核心 2024年第2期307-317,共11页
为揭示河北省典型铅锌矿区重金属来源及生态风险,以河北省某铅锌矿区周边区域为研究对象,通过系统的田间采样采集了156件土壤样品,通过主成分分析(PCA)及正定矩阵因子分解(PMF)模型分析,分析了区域内重金属的来源;运用地累积指数法及潜... 为揭示河北省典型铅锌矿区重金属来源及生态风险,以河北省某铅锌矿区周边区域为研究对象,通过系统的田间采样采集了156件土壤样品,通过主成分分析(PCA)及正定矩阵因子分解(PMF)模型分析,分析了区域内重金属的来源;运用地累积指数法及潜在生态风险指数法进行了风险评价。研究结果表明,Cr,Ni,Cu,Zn,As,Cd,Pb和Hg质量分数平均值分别为53.6,25.7,62.7,692,10.6,1.75,142,0.129 mg/kg,除Cr,Ni和As外,其余5种重金属均处于不同的污染水平,平均值均超河北省土壤背景值,Hg,Cd,Zn,Pb和Cu的变异系数均大于1.75,As的变异系数大于0.5,表明这6种重金属属于高度变异。源解析显示,研究区土壤重金属的主要来源为采矿活动、自然来源、农业活动和金矿冶炼,其中,Pb,Zn和Cd主要源于采矿活动;Cr,Ni主要受自然母质的影响,属于自然来源;Cu主要受农业活动和采矿活动的双重影响;As受自然来源、采矿活动和农业活动三重控制;Hg主要源于金矿冶炼和采矿活动。PCA与PMF模型有机结合、彼此印证,增加了重金属来源解析结果的可信度。研究区存在人为因素引起的Hg和Cd污染,地累积指数和潜在生态风险指数高,生态风险总体属于极高生态风险,需要重点关注并开展治理工作。 展开更多
关键词 重金属 来源解析 统计分析 生态风险 铅锌矿区 河北省
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基于域—生物群系—功能群分类的生态系统类型识别及时空格局变化分析——以河北省太行山区为例
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作者 毕善婷 陈影 +3 位作者 李泽 屈爽 赵文超 梁阅兵 《水土保持通报》 CSCD 北大核心 2024年第2期236-244,257,共10页
[目的]科学识别河北省太行山区生态系统类型,是理解河北省太行山区生态系统时空分布格局和支撑生态系统分类管理的基础。[方法]基于域—生物群系—功能群(RBE)的分类原理,构建了包括3个1级,8个2级和24个3级类的生态系统分类体系,并集成... [目的]科学识别河北省太行山区生态系统类型,是理解河北省太行山区生态系统时空分布格局和支撑生态系统分类管理的基础。[方法]基于域—生物群系—功能群(RBE)的分类原理,构建了包括3个1级,8个2级和24个3级类的生态系统分类体系,并集成多源数据,开展了2000和2020年的河北省太行山区生态系统的分类制图。基于RUSLE模型、InVEST模型和热点分析等方法,分析生态系统服务的时空格局演变。[结果]①河北省太行山区20 a间建设用地生态系统增加最多,主要来自农田生态系统。农田生态系统缩减了61105.95 hm^(2),以雨养农田为主。受人类活动的影响,河流和人工湿地面积分别增加了5584.32和2535.66 hm^(2),而林地和草地生态系统减幅分别为0.96%和8.18%。未利用地生态系统受研究区生态保护措施影响减少5800.68 hm^(2)。②生态系统服务值受生态系统类型分布影响总体呈现西高东低的分布格局,除粮食供给服务为西低东高,主要是由于农田主要分布在东部地区。③冷热点区域空间分布整体上具有重叠性,但仍有差异。[结论]提出的分类体系具有可行性,分类精度达到80%以上,符合研究区的生态系统类型变化趋势,可为识别山区生态系统分类和生态系统保护修复政策提供科学支撑,进而促进山区生态发展目标和可持续发展的实现。 展开更多
关键词 生态系统分类 生态系统服务 时空分布格局 河北省太行山区
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典型流域河流相粉质黏土层物理力学指标相关性分析
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作者 史敬涛 颜翔锦 +4 位作者 田野 王末 王江玉龙 姜禹戈 孙欢 《地质与资源》 CAS 2024年第2期246-253,195,共9页
基于辽宁省辽阳市平原区不同地点、不同深度粉质黏土的土工试验结果,采用一元线性回归分析,对粉质黏土16种物理力学指标的变异性及相互间关系进行数理统计.研究结果表明:1)不同深度、不同地点的土质类型主要是粉质黏土,其含水率较高,且... 基于辽宁省辽阳市平原区不同地点、不同深度粉质黏土的土工试验结果,采用一元线性回归分析,对粉质黏土16种物理力学指标的变异性及相互间关系进行数理统计.研究结果表明:1)不同深度、不同地点的土质类型主要是粉质黏土,其含水率较高,且多呈湿、可塑状态;2)粉质黏土湿密度、天然重度、土粒比重、饱和度、孔隙率、液限、塑限7种物理指标的变异系数均较小,压缩系数、压缩模量、黏聚力、内摩擦角4种力学指标的变异系数较大;3)粉质黏土湿密度与天然重度、液限与塑性指数具有良好的线性关系. 展开更多
关键词 平原区 粉质黏土 土工试验 物理力学指标 回归分析 辽宁省
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河北省张北地区土壤和莜麦重金属含量及健康风险研究
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作者 鲁倩 王雪飞 +4 位作者 车健 马程 余明 边朋沙 张硕 《安徽农业科学》 CAS 2024年第6期81-85,共5页
为探讨河北省张北地区土壤和莜麦中重金属元素含量及健康风险,选择17个适宜采样点进行表层土壤和莜麦籽实样品的采集,通过单因子污染指数法、综合污染指数法和富集系数分别对土壤质量和重金属元素从土壤向莜麦迁移能力进行研究。结果表... 为探讨河北省张北地区土壤和莜麦中重金属元素含量及健康风险,选择17个适宜采样点进行表层土壤和莜麦籽实样品的采集,通过单因子污染指数法、综合污染指数法和富集系数分别对土壤质量和重金属元素从土壤向莜麦迁移能力进行研究。结果表明:研究区土壤和莜麦中重金属含量远低于国家标准,品质安全健康;区内重金属元素在土壤-莜麦系统中富集能力为Zn>Cu>Ni>Cd>As>Pb>Cr=Hg, Ni、Cu和Zn的富集系数远高于Cr、As、Cd、Hg、Pb, Cd迁移能力很弱,As、Pb几乎不发生迁移,Cr、Hg不发生迁移。 展开更多
关键词 重金属元素 含量测定 土壤 莜麦 健康风险 河北省张北地区
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河北省海水养殖业存在的问题与建议
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作者 云天来 赵海涛 +1 位作者 王真真 孙绍永 《河北渔业》 2024年第4期23-29,共7页
从河北省渔业产业、海水养殖面积、产量、产值等分析对比海水养殖业现状,提出当前存在着基础设施及行业发展落后、疾病防控手段不足、科研力量薄弱、水产动物健康和配合饲料普及率不高、产业结构不合理等问题,并提出相应建议:建立无公... 从河北省渔业产业、海水养殖面积、产量、产值等分析对比海水养殖业现状,提出当前存在着基础设施及行业发展落后、疾病防控手段不足、科研力量薄弱、水产动物健康和配合饲料普及率不高、产业结构不合理等问题,并提出相应建议:建立无公害防病及灾害防御机制,研制高效专用配合饲料,加大技术支撑及政策支持,转变养殖方式,优化养殖生产空间,调整渔业产业结构,培养、引进科技人才等。 展开更多
关键词 河北省 海水养殖 面积 产量 产值
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冀北攻坚造林区樟子松幼树叶片功能性状对微地形的响应
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作者 赵浩然 郭忠诚 +3 位作者 张菲 张贺祥 邓婷 刘强 《温带林业研究》 2024年第2期10-16,共7页
【目的】探究冀北山区干旱石质阳坡不同地形对于樟子松幼树叶片功能性状的影响。【方法】以我国北方沙地造林常见树种人工樟子松幼龄林为研究对象,采用样地布设和植被调查的方法,通过方差分析对比幼树的叶面积(LA)、叶长(LL)、叶宽(LW)... 【目的】探究冀北山区干旱石质阳坡不同地形对于樟子松幼树叶片功能性状的影响。【方法】以我国北方沙地造林常见树种人工樟子松幼龄林为研究对象,采用样地布设和植被调查的方法,通过方差分析对比幼树的叶面积(LA)、叶长(LL)、叶宽(LW)、叶曲率(LC)、比叶面积(SLA)、全氮(N)、全磷(P)、全钾(K)、全碳(C)九种叶片功能性状在不同坡度和坡位的差异。【结果】(1)在叶片外部形态方面,平地LL和SLA比坡地显著高出15.25%和5.52%。在叶片养分方面,除C之外,其余养分指标在平地和坡地之间均呈现出显著差异。其中,平地的N、P和K比坡地分别显著高出3.76%、31.14%和9.11%。(2)对于不同坡度,除了LC之外,其余均存在显著差异。LA和LL均表现为陡坡最高,陡坡比中坡平均分别高出20.8%和14.9%;LW表现为缓坡数值最大,分别比陡坡和中坡高出8.9%和5.3%;SLA表现为缓坡和中坡显著比陡坡高出8.6%和8.5%。叶片养分方面全氮含量(N)和全钾含量(K)随着坡度的增加表现出显著下降的趋势,全磷含量(P)则相反,中坡和陡坡显著比缓坡高出31.3%和30.2%。(3)叶片功能性状综合得分排序表明中坡和缓坡地形对樟子松幼树叶片的功能发育有正向促进作用,而陡坡则不利于叶片发育。【结论】本研究综合分析了樟子松幼树叶片功能性状对微地形的响应表现,对集成和优化困难立地植被恢复技术提供一定理论基础。 展开更多
关键词 冀北山区 樟子松 外部形态 叶片养分 微地形
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Pollen assemblages of cultivated vegetation in central and southern Hebei Province 被引量:1
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作者 PANG Ruiming 《Journal of Geographical Sciences》 SCIE CSCD 2011年第3期549-560,共12页
The study on 82 surface soil pollen samples from different types of cultivated vegetations in central and southern parts of Hebei Province indicates that the pollen assem- blages from farmlands in the plain have not o... The study on 82 surface soil pollen samples from different types of cultivated vegetations in central and southern parts of Hebei Province indicates that the pollen assem- blages from farmlands in the plain have not only their own plant types, but also the pollen components from the nearby mountains. Arboreal pollen percentages and concentrations (dominated by Pinus) from farmlands in mountain area are higher than those in the plain, and it reduces gradually with the increasing distance away from the mountains. Taking Pinus pollen in Taihang Mountains as an example, its content is 20%-30%, 10%-20%, 20%-30% and below 16% respectively for the samples from the area of 0-50, 50-100, 100-150 and more than 150 km away from the east Taihang Mountains. The increase of Pinus pollen proportion in the central plain is probably related to the fohn effect. The spatial variation of AP from mountains to the plain in Hebei Province may be similar to the forests clearance by human activities in the early historical period. Shrubby pollen proportion is small both in mountains and in the plain, but their major components are different. Elaeagnaceae, Corylus, Ostryopsis and Oleaceae are common in mountain areas, while there are relatively high contents of Rosaceae and Vitaceae in the plain. Herbs content in the plain (about 60%) is 15% higher than that in mountains, among which the Cereals and Cruciferae pollen percentages are 5% and 2% higher respectively. Artemisia pollen percentage in the plain is lower than that in mountains. Since the human activities are weaker in mountains compared with that in the plain, the general trend is that Chenopodiaceae pollen increases from mountains to the plain gradually, reflecting the raising intensity of human activities. The fern spores of Selaginella sinensis in mountains are higher than that in the plain, but it still reaches to about 7% in the plain. The fern spores of Selaginella sinensis are not prone to be spread by wind, indicating that those in the surface soil of the plain may be carried by river water from mountains during the deposition of the plain. 展开更多
关键词 farmlands human activity pollen assemblages Taihang Mountain plain hebei province
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河北张宣地区中山沟金矿成矿流体特征及其对侵入岩型碲金矿床的限定 被引量:1
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作者 甄世民 查钟健 +8 位作者 王大钊 刘家军 庞振山 程志中 薛建玲 王江 白海军 李阳 陈超 《中国地质》 CAS CSCD 北大核心 2023年第2期605-621,共17页
【研究目的】中山沟金矿位于华北克拉通北缘、尚义—崇礼—赤城深大断裂的南侧,是河北省张宣金矿集区典型金矿床之一。本文探讨了矿床成矿流体特征和演化,以期为该矿床找矿勘查提供理论依据。【研究方法】本文总结了中山沟金矿的成矿背... 【研究目的】中山沟金矿位于华北克拉通北缘、尚义—崇礼—赤城深大断裂的南侧,是河北省张宣金矿集区典型金矿床之一。本文探讨了矿床成矿流体特征和演化,以期为该矿床找矿勘查提供理论依据。【研究方法】本文总结了中山沟金矿的成矿背景、矿区地质特征、矿体及矿石特征,选取4个阶段的代表性样品,开展了流体包裹体岩相学和显微测温、氢氧同位素、氦氩同位素等研究。【研究结果】研究发现中山沟金矿可划分为4个成矿阶段:钾长石-黄铁矿-石英阶段(Ⅰ)、乳白色石英-黄铁矿阶段(Ⅱ)、烟灰色石英-硫化物阶段(Ⅲ)和贫硫化物-碳酸盐阶段(Ⅳ)。各成矿阶段主要发育气液两相原生流体包裹体。流体包裹体测温数据表明,其主成矿阶段均一温度为210~250℃、盐度为6.01%~13.62%NaCleqv。氢、氧同位素研究表明,δ^(18)O水和δDV-SMOW值分别为-2.97‰~6.96‰和-94.6‰~-80.2‰,具有明显向大气降水线发生漂移而呈线性变化的特征。黄铁矿氦、氩同位素研究表明,^(3)He/^(4)He值为1.82×10^(-7)~9.24×10^(-7),^(40)Ar/^(36)Ar值为699.9~2200.4,R/Ra值为0.13~0.66,放射成因^(40)Ar^(*)为55.89%~86.57%,幔源He为2.00%~10.86%。【结论】中山沟金矿成矿流体经历了从中高温、中低盐度至低温、中低盐度的持续演化过程。其主成矿阶段发生了强烈的沸腾作用,成矿晚期有大量的大气降水的混入。随着成矿作用的进行,幔源物质参与成矿的比例逐渐升高。成矿流体具有壳幔混合的特点。综上所述,中山沟金矿的成矿流体具有侵入岩型碲金矿床的特点。 展开更多
关键词 金矿 成矿流体 流体包裹体 同位素 地质调查工程 中山沟 张宣地区 河北
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